Method for constructing reinforced hash function based on compression function

Abstract

The invention belongs to the field of information safety, in particular to the cryptology field, and relates to a method for reinforcing a hash function based on a compression function. The method is used for reinforcing key loops of the hash function, namely reinforcing a first group of the compression function and a final group of the compression function, and increasing the operations of multiple bits or utilizing a present safety group code algorithm by aiming at a majority of operations of a present hash function based on a single bit. The method comprises the following steps of: reinforcing by taking a method of resisting a current differential code analysis and the like as the principal method, also considering about some other attacks, such as a second preimage attack, further adding an input variable in the input of the final group of the compression function, namely a simple compression manner of all group information. The reinforcing method disclosed by the invention has the advantages that when key groups are reinforced, the increase of calculated amount is not large along with the increase of the length of a plaintext; and the decoding obstacle is configured through the most key position, the preimage attack, collision attack, the second preimage attack and the like can be effectively resisted.

Description

technical field [0001] The invention belongs to the field of information security and relates to a method for constructing a one-way hash function based on a compression function. Background technique [0002] At the 2004 International Cryptography Conference, Wang Xiaoyun and others announced the collision results for a series of Hash functions, including MD4, MD5, HAVAL-128 and RIPEMD algorithms, among which the complexity of MD4 and RIPEMD algorithm collisions can be found to be lower than 2 8 and 2 18 . Wang Xiaoyun proposed a new set of analysis techniques for the Hash function of the MDx series. At the same time, he gave a method for satisfying the sufficient conditions of the differential route, and how to use plaintext modification technology to improve the success probability of collision attacks. In 2005, Wang Xiaoyun and others applied this technology to carry out collision attacks on MD5, SHA-0 and SHA-1 algorithms, and achieved good results, and can quickly fi...

AI Technical Summary

Problems solved by technology

The existing hash function is based on an iterative algorithm, and the compression function used for iteration is the same. In this case, there may be some attacks, such as collision attack, preimage attack and second preimage attack, etc.

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